Exercise machine

ABSTRACT

An exercise machine comprises: a mounting frame ( 1 ); at least two user positions ( 18, 181, 205 ); power transmission means ( 2 ) designed to connect corresponding machine actuators ( 3 ) in such a way that the power applied by the users to the actuators ( 3 ) and transmitted by the transmission means ( 2 ) reciprocally and alternately produces an active force and a resistant force.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to an exercise machine, preferablyof isotonic type.

[0002] The fitness sector today offers an extremely wide variety ofexercise machines. These machines can be divided broadly into twocategories: isotonic machines and cardiovascular machines.

[0003] Isotonic machines normally comprise a working position for theuser who uses his/her physical power to apply a force that is opposed bygravity acting on a set of passive elements forming what is normallycalled a weight stack.

[0004] In the present invention, the working position is the locationwhere the user places his/her body, whether seated or standing, whichmeans that this position coincides with an area where the weight of theuser's body is supported by the ground, with or without a footplate.

[0005] Machines of this type have a portal frame which is located in avertical plane and which accommodates a plurality of blocks, each havinga predetermined weight. The user selects the number of blocks to be usedfor the required exercise, thus creating a stack of desired weight whichapplies the resistant force that must be overcome by the user's muscularstrength; between the resistant force and the active part of theexercise apparatus there is usually a connecting element, normallyconsisting of a cord or cable wound several times around pulleys anddesigned to carry the resistant force to the point where the user mustapply his/her physical power to overcome it.

[0006] Thus, in the above type of solution, the resistant force isprovided by gravity. Alternatively, more complex machines may be used inwhich the resistant force is produced by a motor or alternator connectedto a source of electric power and providing controlled torque.

[0007] Whichever the solution adopted, exercise machines of this kind(as generally used for recreational, rehabilitation and similarapplications) are designed in such a way that the user competes againsthimself/herself. In other words, the user has to perform a trainingprotocol without any active opponent, which, in the long run, may leadto deconcentration or even refusal to perform exercises according toestablished rules.

[0008] Another disadvantage is that the correct performance of theprotocol depends entirely on the user and it is therefore difficult tocontrol the uniformity of the training or to assess (unless this is donein separate stages) the individual progress of two or more trainees,such as, for example, the members of a sports team or persons requiredto reach a minimum fitness level.

[0009] The present invention therefore has for an object to overcome theabove mentioned disadvantages by providing an exercise machine thatallows users to train not in isolation but in association with otherusers so as to able to interact with each other while performing anexercise.

SUMMARY OF THE INVENTION

[0010] According to the invention, this object is achieved by anexercise machine as defined in the main appended claim.

[0011] The advantages achieved by the invention lie essentially in thefact that the users training simultaneously on the same machine not onlyfollow a predetermined protocol but also have the opportunity ofmeasuring their strength against each other, thus reducing the risk ofdemotivation and providing a competitive stimulus to achieving thetargets set by the protocol.

[0012] Another advantage is that of permitting the activities ofdifferent trainees following the same or similar training programs to bestandardized, thus making it possible to assess the effectiveness of aprogram on different individuals.

[0013] Further advantages are achieved thanks to the characteristicsdefined in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The technical characteristics of the invention, with reference tothe above aims, are clearly described in the claims below and itsadvantages are apparent from the detailed description which follows,with reference to the accompanying drawings which illustrate preferredembodiments of the invention provided merely by way of example withoutrestricting the scope of the inventive concept, and in which:

[0015]FIG. 1 is a general diagram of an exercise machine according tothe invention;

[0016]FIG. 1a is a diagram showing the connection of adjustable lengthbetween the user positions;

[0017]FIG. 2 is a perspective view of a first preferred embodiment of amachine according to the invention, belonging to the category ofexercise machines generally known as “lat machines”;

[0018]FIG. 3 is a front view of the machine of FIG. 2;

[0019]FIG. 4 is a side view of the machine of FIG. 2;

[0020]FIG. 5 is a perspective view of a second preferred embodiment of amachine according to the invention, belonging to the category ofexercise machines generally known as “upper machines”;

[0021]FIG. 6 is a top view of the machine of FIG. 5;

[0022]FIG. 7 is a side view of the machine of FIG. 5;

[0023]FIG. 8 is a perspective view of a third preferred embodiment of amachine according to the invention, belonging to the category ofexercise machines generally known as “abductor machines”;

[0024]FIG. 9 is a top view of the machine of FIG. 8;

[0025]FIG. 10 is a side view of the machine of FIG. 8;

[0026]FIG. 11 is a perspective view of a fourth preferred embodiment ofa machine according to the invention, resulting from the combination oftwo machines, placed face to face, belonging to the categories ofexercise machines generally known as “chest presses” and “uppermachines”;

[0027]FIG. 12 is a top view of the machine of FIG. 11;

[0028]FIG. 13 is a side view of the machine of FIG. 11;

[0029]FIG. 14 is a graph showing an example curve representing a loadapplied by the users progressively and compared to a reference level;

[0030]FIGS. 15a and 15 b schematically illustrate further embodiments ofthe machine according to the invention;

[0031]FIGS. 16 and 16a-16 c schematically illustrate yet anotherembodiment of the machine according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] With reference to FIG. 1, an exercise machine according to theinvention, in its most general configuration of kinematic components,essentially comprises the following:

[0033] a mounting frame 1;

[0034] a reversible power transmission mechanism 2 mounted on the frame1;

[0035] at least two user work positions equipped with actuators 3operatively connected to the transmission mechanism 2 and designed to beoperated by the users who alternately and reciprocally apply an activeforce and a resistant force through the transmission mechanism 2.

[0036] Advantageously, as shown in the diagram of FIG. 1, thetransmission mechanism may consist wholly or partly of a set of rigidlevers joined to each other and, if necessary, combined with cablemechanisms, as described in more detail below.

[0037] In all its preferred embodiments, the machine is preferablyequipped with a load sensor designed to indicate a value (and, ifnecessary, a threshold) of the force load applied by the users.

[0038]FIG. 1a schematically illustrates the connection between the userpositions. The length of the connection can be adjusted by means of amotor M designed to move the pin 23×of a pulley 22 vertically in thedirection indicated by the arrow F, thus shifting the actuators betweenthe initial positions 3 and 3 a.

[0039] Preferably, the cable 24 is also equipped with load sensors 224,load cells 226 and dampers 225.

[0040]FIG. 14 is a graph showing an example curve representing the loadC applied by the user, measured by a sensor and displayed by a displayunit indicated schematically by the reference letter D in FIG. 14,compared to a reference level R representing the training program, insuch a way as to stimulate the users, individually and in competitionwith each other, to keep up with the program.

[0041] Still with reference to FIG. 14, the invention also contemplatesthe possibility of a progressive indication of the load C by the displayunit D or by a separate unit in order to enable the users to check thelevel they have reached at any point in time.

[0042] It should be stressed that all the embodiments described beloware offered purely as examples of the inventive concept without therebylimiting the possibility of extending the concept to other solutions,all falling within the scope of the appended claims. This is intended asconfirmation of the possibility of extending the inventive concept to awide range of different machines.

[0043] With reference to the embodiment illustrated in FIGS. 2 to 4, themachine frame consists of a portal frame 11 supported at the bottom by abase 19 and having, at the top of it, a crossbeam 12 mounted in turn ona forked support 131.

[0044] The work position of each user consists of a seat 18 and rollers17 adjustable in height by means of a telescopic support 171 that can belocked in a desired location by a height selector block 172.

[0045] The rollers 17 are preferably covered with soft padding and usedto hold down the legs of the users sitting in the seats 18.

[0046] The power transmission mechanism consists of a system of pulleys22 rotating on pins 23 fixed to the crossbeam 12, and having trainedaround them a flexible cable 24 with a handlebar 30 at each end,preferably of ergonomic form to facilitate gripping by the users.

[0047] During use, the two users sitting in the seats 18 with therollers 17 resting on their legs in such a way that they can grip theactuators 30 with both hands and alternately apply a force (according toa well-known training technique) which is transmitted to the other userthrough the cable 24.

[0048] In this way, one of the two users applies an active force whilstthe other exerts a resistant force, if necessary according to apredetermined training protocol.

[0049] Preferably, a load sensor 241, located for example on the cable24, indicates when the load reaches a predetermined threshold value setfor safety reasons and/or as a check on the exercise being performed.

[0050] With reference to the embodiment illustrated in FIGS. 5 to 7, themachine frame consists of an upturned U structure 11 supported at thebottom by a beam 101 and a crossbeam 102.

[0051] Mounted on the beam 101 there are two pairs of uprights, thefirst pair 103 being vertical and the second pair 104 being slightlyinclined and upwardly converging.

[0052] The two pairs of uprights 103, 104 are joined at the top of theframe by respective bars 105, which are slightly inclined to thehorizontal and converge at the center of the frame where they join the Ustructure 100.

[0053] Each of the user work positions consists of a seat 181,adjustably mounted for height along the upright 104, and a rest 173 forthe user's chest.

[0054] The distance of the chest rest 173 from the user can be adjustedby operating on a support 174 that slides inside the bars 105 and can belocked in a desired position using customary selective lock devices 175.

[0055] At the height of the adjustable support 174, the bars 105 mountcurved arms 106 facing the user position and having two joints 107fitted at the ends of them.

[0056] The joints 107 have pivoted on them the first ends of a pair ofhandlebars 108 each of which is fitted with a handle 109 at the otherend.

[0057] The handlebars 108 are mounted crossways relative to each otherand can be rotated towards each other by the user.

[0058] The power transmission mechanism consists of cables—notillustrated in the drawings—which start at the joints 107 and runpreferably inside the components of the frame to connect, throughcustomary pulley type devices, the pair of handlebars 108 of one userwork position with the pair of handlebars 108 of the other user workposition.

[0059] During use, the users sit in the seats 181 gripping the handles109 and move the latter alternately to and fro, if necessary accordingto a predetermined training protocol. In other terms, while one of theusers exerts an active force and pulls the handlebars 108 towardshimself/herself, the other applies a resistant force to oppose thisaction.

[0060] With reference to the embodiment illustrated in FIGS. 8 to 10,the machine frame consists of a U-shaped structure 201 supported at thebottom by a main beam 202 and a crossbeam 203.

[0061] Symmetrically mounted at the ends of the main beam 202, there aretwo curved uprights 204 each fitted with a seat 205 fixed to an upperhorizontal section 206 of the upright 204 itself.

[0062] Under each seat 205 there extend two shafts 207 which are fixedat the bottom to a transversal support 219 and about which twostructures 208 rotate symmetrically in such a way as to resist theoutward movement of the legs of the users sitting in the seats 205.

[0063] Looking in more detail, each of the structures 208 consists of anapproximately horizontal arm 210 which can rotate with a first end abouta shaft 207 and which, at the other end, is attached to the intermediatevertical section 213 of a bar 211.

[0064] The bar 211 has an upper horizontal section 214, to which thereis fixed a rest or pad 215 for engaging the user's thighs, and a lowerinclined section 216 fitted with a footrest 217.

[0065] At the sides of each seat 205 there are handles 218, which theuser holds for stability, and an adjustment lever 220.

[0066] The power transmission mechanism between the two user workpositions consists of a system of cables (not illustrated in thedrawings since it is of known type) that run preferably inside thecomponents of the frame to connect the opening movement of thestructures 208 of one work position to the corresponding closingmovement of the levers 208 of the other work position.

[0067] Thus, while one user spreads his/her legs outwards against thethigh pads 218 exerting an active force that opens the structures 208,the other user may apply a resistant force. This exercise may form partof a predetermined training protocol.

[0068] With reference to the embodiment illustrated in FIGS. 11 to 13,the machine frame is divided into two halves, one like the framedescribed above with reference to FIGS. 5 to 8 (the correspondingcomponents are thus labeled with the same reference numbers) facing theother half consisting of a side upright 301 fixed at the bottom to thebeam 101 and joined by an intermediate section 302 to a second upright303, also fixed to the bottom beam 101.

[0069] The upper end of the upright 301 has a crossbeam 309 that iscurved inwardly with its concave section facing the center of themachine.

[0070] The user work position is mounted on the upright 303 and consistsof a seat, adjustably mounted for height on the upright 303, and abackrest 305 fixed to the upright 303.

[0071] The actuators in this case consist of a pair of arms 308 mountedcrossways and able to counter-rotate about pins located at the ends ofthe crossbeam 309.

[0072] The arms 308 are also fitted with customary handgrips 310.

[0073] The power transmission mechanism consists of a pulley and cablesystem 311 partly installed on the crossbeam 309 and not described inany detail since it is of well known type.

[0074] According to the invention, the transmission mechanism is suchthat, starting at the end 308 the force exerted by the user at the workposition 304 is transmitted to the actuators 108 of the user position181 and vice versa.

[0075] As in the other preferred embodiments described above, the cablesof the transmission mechanism may follow a different path, runningpreferably inside the components (preferably tubular) of the machineframe.

[0076] Moreover, in all the embodiments, the means for connecting theuser positions may comprise means for adjusting the length of theconnection according to the physical characteristics of the users.

[0077] The connecting means may also include elastic means or dampers tosmooth the transient effects of passing from an active force to aresistant force and vice versa.

[0078]FIGS. 16, 16a and 16 b illustrate yet another embodiment of theinvention.

[0079] The machine comprises a base 401 mounting an upright 400consisting preferably of a tube, for example with an oval cross section,acting as a guide for a work unit 404.

[0080] Advantageously, the single upright structure 403 enables theusers to move all the way round the machine and to change theirpositions relative to the actuators to perform different exercises.

[0081] The work unit 404, slidable along the guide 403, may be fixed inposition by a locking element 405, consisting, for example, of a clampscrew that moves as one with the work unit 404 and engages by contact orinterference with the vertical guide 403.

[0082] At the top end 420 of the upright 400 there are two pulleys 409positioned horizontally side by side, whilst another two transmissionpulleys 410 are positioned at the bottom end, close to the base 401.

[0083] The sliding work unit 404 is in turn equipped with four pairs ofopposing horizontal plates 406, between which there are mounted,preferably rotating about horizontal axes, four supports 408 arranged inpairs on opposite sides of the upright 403 and each mounting a pair ofpulleys 407 with horizontal axes and positioned over each othervertically.

[0084] Advantageously, the rotation of the supports enables users toeasily perform exercises requiring the actuators to be moved apart aswell as exercises in which the users have to change their positionsrelative to the actuators by moving around the machine.

[0085] In the embodiment illustrated, the work unit 404 mounts all thepulleys 407 which are therefore adjustable as one.

[0086] It will be understood, however, that the invention alsocontemplates that the height of the pulleys might also be adjustedindependently at the two sides of the upright, in such manner as toindividually vary one or both of the pulling points of one or both ofthe users.

[0087] The machine also comprises two cables 412, 412′ passing throughrespective pulleys 407, 409, 410 and actuated by opposite pairs ofhandles 414 a/414 b and 415 a/415 b operated by two users (notillustrated in the drawings) standing on opposite sides of the upright403 at the schematically illustrated exercise positions labeled 413.

[0088] It will be understood that the handles might be substituted byactuators or handlebars of any kind suitable for performing theexercise.

[0089] Looking in more detail, the cables 412, 412′ constitute atwin-cable arrangement, that is to say, a double path of twin cableseach of which, with reference, for example, to the cable 412, is fixedat one end to a first actuator 414 a, passes through the overlaidpulleys 407 of one support 408 positioned at a first side of the upright403 and, in succession, through the corresponding upper and lowerpulleys 409 and 410 to connect up with the opposite actuator 414 b afterpassing through the central overlaid pulleys 407 of the support 408 atthe opposite side of the upright 403.

[0090] An identical path through the corresponding central, upper andlower pulleys 407, 409 and 410, is followed by the second cable 412′which connects the opposing actuator 415 a and 415 b.

[0091] In the embodiment being described, there are two of each of thepulleys 407, 409, 410 on each side of the machine so as to enable twousers to exercise both arms at the same time, but without therebyexcluding the possibility of having a single pulley or more than twopulleys, according to requirements.

[0092] During operation, the two users, each in his/her exerciseposition 413, grip the actuators on the corresponding side of themachine, and alternately pull the two actuators (for example, 414 a and415 a) in such that the two users, thanks to the path followed by thecables 412 and 412′, oppose each other in alternately pulling theactuators.

[0093] On a machine constructed in this way, the two users may oppose orsecond each other in performing different types of exercises for thepurposes of muscular strengthening, cardiovascular training, muscularstretching or even proprioceptive training in which one of the two userstests the balance of the other.

[0094] Further, thanks to the adjustability of the vertical position ofthe work unit 404 and to the rotatability of the supports 408, the pointand angle at which the cable is pulled outwards, that is to say, thedirection of the force applied by the users, can be varied according tothe type of exercise and to the part of the body to be exercised.

[0095] It follows that the upper or the lower pulley in the pairs ofpulleys 407 mounted on the work unit 404 is activated according to theposition of the work unit relative to the user's grip.

[0096] Further, the length of the cables 412/412′ pulled out of themachine can be adjusted to suit the type of exercise which the usershave to perform, and according to the distance from the machine requiredby the exercise.

[0097] Looking in more detail, the length of the cable 412/412′ that canbe pulled out of the machine can be adjusted by making the cable followa path such that, on leaving the lower pulley 410, it winds one or moretimes around a corresponding pulley 419, mounted on idle rollers on theupright 403 and then proceeds along the path described above towards theupper pulley 409 and from there to the opposite actuator.

[0098] With this solution, each turn around the pulley 419 correspondsto a reduction of the active length of the cable 412/412′, that is tosay, the extent to which the cable can be pulled out of the machineusing the opposite actuator 414 a,b and 415 a,b.

[0099] According to another characteristic of the machine, the upperpulleys 409 are mounted in a protective guard 427 and are connected to adynamo 423 which powers a lamp 422 located above the user work positions413.

[0100] When the lamp switches on, it provides an indication of the speedat which the exercise is being carried out and may also constitute aperformance target to be achieved.

[0101] In addition, the base 401, which must normally have a certainweight to guarantee machine stability, may consist of a hollow container426 equipped with a filler opening 425, so that the machine itself isrelatively light for transportation purposes but, once positioned, canbe weighted down by filling the container with liquid (or sand or othersuitable material) to increase the stability of the machine during use.To facilitate handling, the machine of FIG. 16 may also be equipped withwheels 424 fitted to the edge of the base 401 slightly off the ground soas to touch the ground only if the upright 403 is tilted to enable it tobe moved from one place to another.

[0102] In the embodiments described above, an additional resistantforce, consisting, for example, of traditional weights, may be appliedto one or both sides of the machine besides the alternateactive/resistant force applied by the users. This would compensate forexcessive differences in strength between the two users.

[0103] By way of example, FIGS. 15a and 14 b schematically illustrate amachine according to the invention in which a set of weights P, variablein number and composition according to requirements, is applied to oneof two user positions.

[0104] In the embodiment of FIG. 15a, the weights are positioned closeto one of the actuators 3, so as to increase the resistant force appliedto the other actuator.

[0105] In FIG. 15b the weights P are applied to one of the two actuatorsby means of an additional system of cables 24 and pulleys 22.

[0106] Looking in more detail at the embodiment illustrated in FIG. 15b,the pulleys of the additional system have two grooves so that theactuator concerned is connected to the other actuator through a firstcable 24 passing around one groove in the pulleys 22 and to the weightstack P through a second cable passing around the other groove in thesame pulleys.

[0107] Obviously, the weight stack P may be varied according torequirements and may be applied to one or both user positions.

[0108]FIG. 15b also shows a load cell CC advantageously applied to apoint 29 where one of the pulleys 22 is fixed to the frame 1.

[0109] In this case, the load cell is applied to the point where thepulley located at the center of symmetry is attached to the frame but itmay be fitted at any other suitable position.

[0110] This solution offers the advantage of measuring the load in astructurally and functionally simple manner.

[0111] The invention described has evident industrial applications andcan be subject to modifications and variations without thereby departingfrom the scope of the inventive concept. Moreover, all the details ofthe invention may be substituted by technically equivalent elements.

What is claimed is:
 1. An exercise machine comprising: a mounting frame(1); at least two user positions (18, 181, 205, 413); power transmissionmeans (2) designed to connect corresponding machine actuators (3) andaccessible by the users in such a way that the power applied by theusers on one or more of the actuators (3) is transmitted by thetransmission means (2) to one or more of the remaining actuators andreciprocally and alternately constitutes for the users an active forceand a resistant force for moving the actuators relative to the userpositions.
 2. The machine according to claim 1, wherein: the frame (1)consists of a portal frame (11) supported at the bottom by a base (19)and having, at the top of it, a crossbeam (12); each user positionconsists of a seat (18) and upper rest rollers (17); the transmissionmechanism (2) consists of a system of pulleys (22) rotating on pins (23)fixed to the crossbeam (12), and having trained around them a flexiblecable (24) with a handlebar (30) at each end where the user workpositions are.
 3. The machine according to claim 2, wherein the rollers(17) are made of soft material and can be adjusted in height by means ofa telescopic support (171) that can be locked in a desired positionusing a height selector block (172).
 4. The machine according to claim2, comprising force detecting means consisting of a load sensor (241)located on the cable (24) and designed to indicate when the load reachesa predetermined threshold value.
 5. The machine according to claim 1,wherein: the frame consists of an upturned U-shaped structure (100)supported at the bottom by a beam (101) and a crossbeam (102), on whichthere are mounted two pairs of uprights, the first pair (103) beingvertical and the second pair (104) being inclined and upwardlyconverging, joined at the top of the frame by respective bars (105),which converge at the center of the frame where they join the upturned Ustructure (100); each user work position consists of a seat (181) fixedto a respective upright (104) and a rest (173) for the user's chestfixed to a respective upper bar (105); the actuators consist of curvedarms (106) facing the user position and having two joints (107) fittedat the ends of them, which have pivoted on them the first ends of a pairof handlebars (108) each of which is fitted with a handle (109) andwhich are mounted crossways relative to each other and can be rotatedtowards each other by the user; the transmission mechanism consists of asystem of pulleys and cables extending from the joints (107) and throughthe arms (106) and the bars (105) to connect the pair of handlebars(108) of one user work position with the pair of handlebars (108) of theother user work position.
 6. The machine according to claim 5, whereinthe seat (181) is adjustably mounted for height on the upright (104) andthe chest rest (173) is adjustably mounted for distance from the user bymeans of a support (174) that slides inside the bars (105).
 7. Themachine according to claim 5, comprising force detecting meansconsisting of a load sensor located on the cable and designed toindicate when the load reaches a predetermined threshold value.
 8. Themachine according to claim 1, wherein: the frame consists of a U-shapedstructure (201) supported at the bottom by a main beam (202) and acrossbeam (203), the main beam (202) having mounted at the ends of ittwo curved uprights (204) with an upper horizontal section (206); eachuser work position consists of a seat (205) mounted on the horizontalsection (206) of the uprights (204); each actuator consists of a pair ofshafts (207) fixed at the bottom to a transversal support (219) andabout which two structures (208) rotate symmetrically in such a way asto resist the spreading out movement of the legs of the users sitting inthe seats (205); the power transmission mechanism consists of a systemof pulley and cables passing through the shafts (207) and the beam (202)in such a way as to connect the opening movement of the structure (208)at one user work position to the corresponding closing movement of thestructure (208) at the other user work position.
 9. The machineaccording to claim 8, wherein each of the structures (208) consists of apair of arms (210) which can rotate with a first end about a shaft (207)and which, at the other end, is attached to the intermediate verticalsection (213) of a bar (211) having an upper horizontal section (214) towhich there is fixed a rest (215) for engaging the user's thighs, and alower inclined section (216) fitted with a footrest (217).
 10. Themachine according to claim 8, wherein at the sides of each seat (205)there are handles (218), which the user holds for stability, and anadjustment lever (220).
 11. The machine according to claim 1, wherein:the frame consists of an upturned U-shaped structure (100) supported atthe bottom by a beam (101) and a crossbeam (102), at one end of whichthere are mounted two uprights, the first (103) being vertical and thesecond (104) being inclined and upwardly converging, the uprights beingjoined at the top of the frame by a bar (105), which joins the U-shapedstructure (100) at the center of the frame, the second end of the beam(101) having mounted on it a side upright (301) fixed at the bottom tothe beam (101) and joined by an intermediate section (302) to a secondupright (303), also fixed to the bottom beam (101), where the upper endof the upright (301) has a crossbeam (309) that is curved inwardly withits concave section facing the center of the machine; the first userwork position consists of a seat (181) fixed to a respective upright(104) and a rest (173) for the user's chest fixed to a respective upperbar (105) and the second user work position consists of a seat,adjustably mounted for height on the upright (303) and a backrest (305)fixed to the upright (303); the first actuator consists of curved arms(106) facing the user position and having two joints (107) fitted at theends of them, which have pivoted on them the first ends of a pair ofhandlebars (108) each of which is fitted with a handle (109) and whichare mounted crossways relative to each other and can be rotated towardseach other by the user, and the second actuator consists of a pair ofarms (308) mounted crossways and able to counter-rotate about pinslocated at the ends of the crossbeam (309); the transmission mechanismconsists of a system of pulleys and cables extending in successionthrough the frame to connect the pair of handlebars (108) of one userwork position with the pair of arms (308) of the other user workposition.
 12. The machine according to claim 1, wherein the framecomprises an upright (403) and the transmission means consist of atleast one cable (412, 412′) passing in succession through a plurality ofpulleys; the actuating means consisting of at least two handles (414a,b; 415 a,b) fitted at the ends of the cable (412, 412′) on each sideof the upright (403) for use by at least two users in their respectivework positions (413). 13 The machine according to claim 12, comprising afirst and a second cable (412, 412′) having handles at their ends, sothat two pair of handles (414 a-415 a; 414 b-415 b) are available at tworespective user work positions (413), each of said pair of handles beingformed by two handles which are fitted respectively to an end of saidfirst and of said second cable (412, 412′).
 14. The machine according toclaim 12 or 13, wherein the plurality of pulleys comprises an initialpulley (407) mounted on the upright (403), at least one intermediatepulley (409, 410) vertically offset from the first pulley and an endpulley (407) mounted on the upright (403) and vertically offset from theintermediate pulley.
 15. The machine according to claim 14, whereineither the initial or the end pulley (407) or both are adjustablymounted for height on the upright.
 16. The machine according to claim15, wherein the initial and end pulleys (407) are adjustable in heightindependently of each other.
 17. The machine according to claim 14,wherein the upright consists of a central tubular element (403) on whichthere slides a work unit (404) mounting the initial and end pulleys(407) and comprising at least two pairs of handles (414 a-415 a; 414b-415 b) fitted at respective user work positions (413) at therespective ends of two transmission cables (412, 412′).
 18. The machineaccording to claim 1, wherein at the connecting means there are means(214, 216) for detecting the applied force designed to detect a valueproportional to the force itself and to send it to display means. 19.The machine according to claim 18, wherein the detecting means consistof an extensometric cell connected in series on a cable.
 20. The machineaccording to claim 1, wherein the means for connecting the actuators (3)comprise means (M, 23×, 419) for correcting their length according tothe physical characteristics of the users.
 21. The machine according toclaim 1, wherein the connecting means comprise elastic or damping meansdesigned to smooth the transient effects of passing from an active forceto a resistant force and vice versa.
 22. The machine according to claim1, comprising force detecting means consisting of one or more loadsensors (214, 216) located on a cable or joint and designed to indicatewhen a predetermined load has been reached.
 23. The machine according toclaim 1, comprising a device (D) for displaying the level of the load(C) reached, as a progressive value or as a value compared to areference level (R) representing the training program.
 24. The machineaccording to claim 1, comprising additional means for applying aresistant force to oppose the active force exerted by a user on one ormore actuators.
 25. The machine according to claim 23, wherein theadditional resistant means consist of one or more weights (P) applied tothe actuator (3) of at least one of the user work positions in such away as to increase the resistant force exerted on the other actuators.26. The machine according to claim 24, wherein the additional resistantmeans consist of one or more weights (P) applied to one of the twoactuators by means of an additional system of cables and pulleys. 27.The machine according to claim 2, comprising a load cell (CC) applied toa point (29) where one of the pulleys (22) is fixed to the frame (1).28. The machine according to claim 1, wherein the connecting meanscomprise means (215) for damping the load.
 29. The machine according toclaim 1, wherein the connecting means comprise articulated levers (2)and/or pulley systems (22) with one or more cables (24) connecting theactuators (3).